
var turnplate = {
    restaraunts: [], //大转盘奖品名称
    colors: [], //大转盘奖品区块对应背景颜色
    outsideRadius: 192, //大转盘外圆的半径
    textRadius: 155, //大转盘奖品位置距离圆心的距离
    insideRadius: 68, //大转盘内圆的半径
    startAngle: 0, //开始角度

    bRotate: false //false:停止;ture:旋转
};

$(document).ready(function() {
    //动态添加大转盘的奖品与奖品区域背景颜色
    turnplate.restaraunts = ["50M免费流量包", "10闪币", "谢谢参与", "5闪币", "10M免费流量包", "20M免费流量包", "20闪币 ", "30M免费流量包", "100M免费流量包", "2闪币"];
    turnplate.colors = ["#FFF4D6", "#FFFFFF", "#FFF4D6", "#FFFFFF", "#FFF4D6", "#FFFFFF", "#FFF4D6", "#FFFFFF", "#FFF4D6", "#FFFFFF"];

    var rotateTimeOut = function() {
        $('#wheelcanvas').rotate({
            angle: 0,
            animateTo: 2160,
            duration: 8000,
            callback: function() {
                alert('网络超时，请检查您的网络设置！');
            }
        });
    };


    //在页面不可以点击，如需要打开注释
    $('.pointer').click(function() {
        if(turnplate.bRotate) return;
        turnplate.bRotate = !turnplate.bRotate;
        //获取随机数(奖品个数范围内)
        var item = rnd(1, turnplate.restaraunts.length);
        //奖品数量等于10,指针落在对应奖品区域的中心角度[252, 216, 180, 144, 108, 72, 36, 360, 324, 288]
        rotateFn(item, turnplate.restaraunts[item - 1]);
        /* switch (item) {
            case 1:
                rotateFn(252, turnplate.restaraunts[0]);
                break;
            case 2:
                rotateFn(216, turnplate.restaraunts[1]);
                break;
            case 3:
                rotateFn(180, turnplate.restaraunts[2]);
                break;
            case 4:
                rotateFn(144, turnplate.restaraunts[3]);
                break;
            case 5:
                rotateFn(108, turnplate.restaraunts[4]);
                break;
            case 6:
                rotateFn(72, turnplate.restaraunts[5]);
                break;
            case 7:
                rotateFn(36, turnplate.restaraunts[6]);
                break;
            case 8:
                rotateFn(360, turnplate.restaraunts[7]);
                break;
            case 9:
                rotateFn(324, turnplate.restaraunts[8]);
                break;
            case 10:
                rotateFn(288, turnplate.restaraunts[9]);
                break;
        } */
        console.log(item);
    });

});


//旋转转盘 item:奖品位置; txt：提示语;
function rotateFn(item, txt) {
    var angles = item * (360 / turnplate.restaraunts.length) - (360 / (turnplate.restaraunts.length * 2));

    if(angles <= 270 ) {
        angles = 270 - angles;
    } else {
        angles = 360 - angles + 270;
    }

    $('#wheelcanvas').stopRotate();
    $('#wheelcanvas').rotate({
        angle: 0,
        animateTo: angles + 1800,
        duration: 8000,
        callback: function() {
            //alert(txt);
            turnplate.bRotate = !turnplate.bRotate;
        }
    });
};


function rnd(n, m) {
    var random = Math.floor(Math.random() * (m - n + 1) + n);
    return random;

}

//页面所有元素加载完毕后执行drawRouletteWheel()方法对转盘进行渲染
window.onload = function() {
    drawRouletteWheel();
};

function drawRouletteWheel() {
    var canvas = document.getElementById("wheelcanvas");
    if(canvas.getContext) {
        //根据奖品个数计算圆周角度
        var arc = Math.PI / (turnplate.restaraunts.length / 2);
        var ctx = canvas.getContext("2d");
        //在给定矩形内清空一个矩形
        ctx.clearRect(0, 0, 422, 422);
        //strokeStyle 属性设置或返回用于笔触的颜色、渐变或模式
        ctx.strokeStyle = "#FFBE04";
        //font 属性设置或返回画布上文本内容的当前字体属性
        ctx.font = '16px Microsoft YaHei';
        for(var i = 0; i < turnplate.restaraunts.length; i++) {
            var angle = turnplate.startAngle + i * arc;
            ctx.fillStyle = turnplate.colors[i];
            ctx.beginPath();
            //arc(x,y,r,起始角,结束角,绘制方向) 方法创建弧/曲线（用于创建圆或部分圆）
            ctx.arc(211, 211, turnplate.outsideRadius, angle, angle + arc, false);
            ctx.arc(211, 211, turnplate.insideRadius, angle + arc, angle, true);
            ctx.stroke();
            ctx.fill();
            //锁画布(为了保存之前的画布状态)
            ctx.save();

            //----绘制奖品开始----
            ctx.fillStyle = "#E5302F";
            var text = turnplate.restaraunts[i];
            var line_height = 17;
            //translate方法重新映射画布上的 (0,0) 位置
            ctx.translate(211 + Math.cos(angle + arc / 2) * turnplate.textRadius, 211 + Math.sin(angle + arc / 2) * turnplate.textRadius);

            //rotate方法旋转当前的绘图
            ctx.rotate(angle + arc / 2 + Math.PI / 2);

            /** 下面代码根据奖品类型、奖品名称长度渲染不同效果，如字体、颜色、图片效果。(具体根据实际情况改变) **/
            if(text.indexOf("M") > 0) { //流量包
                var texts = text.split("M");
                for(var j = 0; j < texts.length; j++) {
                    ctx.font = j == 0 ? 'bold 20px Microsoft YaHei' : '16px Microsoft YaHei';
                    if(j == 0) {
                        ctx.fillText(texts[j] + "M", -ctx.measureText(texts[j] + "M").width / 2, j * line_height);
                    } else {
                        ctx.fillText(texts[j], -ctx.measureText(texts[j]).width / 2, j * line_height);
                    }
                }
            } else if(text.indexOf("M") == -1 && text.length > 6) { //奖品名称长度超过一定范围
                text = text.substring(0, 6) + "||" + text.substring(6);
                var texts = text.split("||");
                for(var j = 0; j < texts.length; j++) {
                    ctx.fillText(texts[j], -ctx.measureText(texts[j]).width / 2, j * line_height);
                }
            } else {
                //在画布上绘制填色的文本。文本的默认颜色是黑色
                //measureText()方法返回包含一个对象，该对象包含以像素计的指定字体宽度
                ctx.fillText(text, -ctx.measureText(text).width / 2, 0);
            }

            //添加对应图标
            if(text.indexOf("闪币") > 0) {
                var img = document.getElementById("shan-img");
                img.onload = function() {
                    ctx.drawImage(img, -15, 10);
                };
                ctx.drawImage(img, -15, 10);
            } else if(text.indexOf("谢谢参与") >= 0) {
                var img = document.getElementById("sorry-img");
                img.onload = function() {
                    ctx.drawImage(img, -15, 10);
                };
                ctx.drawImage(img, -15, 10);
            }
            //把当前画布返回（调整）到上一个save()状态之前
            ctx.restore();
            //----绘制奖品结束----
        }
    }
}